CloverBootloader/MdePkg/Library/BaseLib/Ia32/WriteDr4.c

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/** @file
AsmWriteDr4 function
Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
/**
Writes a value to Debug Register 4 (DR4).
Writes and returns a new value to DR4. This function is only available on
IA-32 and x64. This writes a 32-bit value on IA-32 and a 64-bit value on x64.
@param Value The value to write to Dr4.
@return The value written to Debug Register 4 (DR4).
**/
UINTN
EFIAPI
AsmWriteDr4 (
IN UINTN Value
)
{
_asm {
mov eax, Value
_emit 0x0f // mov dr4, eax
_emit 0x23
_emit 0xe0
}
}